Metal furniture



June 16, 1953 w GRABENDlKE 2,642,126

METAL FURNITURE Filed Jan. v, 1948 I 2 Sheets-Sheet 1 O I 0 m 0 W1LL1AM E GRABENDIKE.

INVENTOR. o 0 1 WW II/ BY ATTORNLY.

June 1953 w. F. GRABENDIKE 2,642,126

METAL FURNITURE 2 Sheets-Sheet 2 Filed Jan. 7, 1948 75 WILLIAM F. GRABENDIKE INVENTOR.

ATTORN Y.

Patented June 16, 1953 UNITED STAS OFFICE METAL FURNITURE Application January 7, 1948, Serial No. 953

able to eliminate leg bracing, both in tables and chairs. To eliminate such bracing it is necessary to first fabricate a highly rigid weight supporting platform to which rigid metal legs are subse- 9 Claims. (01. 155-194) quently secured. While this type of furniture has been made for many years, and while numerous improvements have been made in its design during these years, the rigid weight supporting platforms must, up to this time, be made relatively deep, and must be made from heavy gage low carbon sheet steel in order to obtain the desired rigidity. In addition, the manufacturers of this type of furniture still find it necessary to use internal diagonal cross bracing between opposite corners of the weight Supporting platform to eliminate flexing of the side walls of the platform. Cross bracing of the'legs below the platform is also standard practice. Such structures are both difficult and costly to fabricate. In addition, they make the article of furniture very heavy.

It is the chief object of this invention to provide a highly rigid weight supporting platform for metal furniture which is so designed that it can be made of light gage sheet aluminum instead of heavy gage sheet steel.

It is a further object to provide such rigidity in a platform of this type that internal corner to corner cross bracing may be eliminated.

A further object is to provide a weightsupporting platform construction for chairs, tables, beds, etc., which eliminates the necessity of providing rungs or cross braces of any kind between the supporting legs.

Another object is to provide a rigid metal understructure for a table or the like, which may subsequently be fitted with a table top of desired material, such as a finely finished wooden panel, a laminated plasticpanel, etc.

Another object is to provide a rigid metal understructure for a chair which may be completely assembled before the padding and upholstery are applied to the seat and back, yet which is so designed that, if desired, the metal frame for the back may be completely fabricated and the padding and upholstery applied before the back is attached to the weight supporting unit,

Another prime object of the invention is to provide a rigid understructure for metal furniture which is much less expensive to fabricate than such structures as are presently in use, which is much lighter in weight than present day structures, and which can be made of material which is much more resistant to corrosion than material which is presently in use, consequently giving the furniture much longer life in humid or tropical climates.

These and further objects of the invention will be more clearly understood when the following specifications are read in connection with the accompanying drawings, which are for i1- lustrative purposes only, and in which:

Figure 1 is a plan view of a drawn sheet metal pan comprising a part of one embodiment of the invention;

Figure 2 is a longitudinal sectional view of this pan taken along the .line 22 of Figure 1;

Figure 3 is a plan View of a sheet metal panel, which is another part of the same embodiment of the invention;

Figure 4 is a plan view of an assembled chair frame embodying the invention;

Figure 5 is a vertical section of this chair frame taken along the line 55 of Figure 4;

Figure 6 is a fragmentary isometric view showing certain details of chair leg construction;

Figure 7 is a fragmentary sectional view showing in detail one manner of upholstering a chair seat which has been constructed in accordance with the invention; V

Figure 8 is a perspective view of the chair back assembly includedin Figures 4 and 5;

Figure 9 is a longitudinal sectional view of a table illustrating another embodiment of the invention;

- Figures 10 and 11 are lateral sectional views of different types of tables embodying the invention; V

Figure 12 is a perspective view of a brace member used in the table of Figure 11; and

Figure 13 is a longitudinal sectional view of a theater seat embodying the invention.

Brief general description In general, the invention comprises a rigid weight supporting platform to which suitable legs may be secured in various manners to form a table underframe, or to which legs and a back may be secured to form a chair frame. The rigid platform is made up of a one piece drawn sheet metal pan having a flat or beaded bottom and a continuous depending sidewall, together with a fiat or beaded sheet metal panel rigidly attached at its edges to the free edge of the sidewall of the pan. This means that the pan can usually be drawn in one machine operation, the panel can be stamped in one machine operation, and the joinder of the two can be accomplished very quickly by a spot welding or riveting machine. The unit thus formed is highly rigid because a closed, box type, stressed skin structure is formedthe pan bottom, the sidewalls, and the panel each brace the others against flexing in any direction. Legs are attached either directly to the panel, to the sidewall of the pan, to the pan bottom, to any two of these elements, or to all three of them. The rigidity of the construction makes it possible to use much lighter gage sheet metal, and also to use a material which has much less inherent rigidity than the sheet steel now used for such purposes.

. Detailed description The rigid weight supporting platform, which is a basic part of the invention, is made up of a drawn sheet metal pan i (Figs. 1 and 2), and a sheet metal panel l5 (Fig. 3). In the illustrations shown these two elements are shaped to form a weight supporting bottom for a chair. As will be seen, the pan has a flat bottom ll, which is beaded as at it for additional rigidity. It has integral continuous sidewalls 19, which in this instance are provided with a continuous integral outwardly turned flange 2d. This pan may be made in any desired shape depending on the type or chair desired. It will be noted that the center bead in the bottom of this pan is widened and perforated, as at 2| and 22, to permit the installation of nut plates at these joints. The curved rear wall of the pan is indented, as indicated by the numerals 23 and 2d, and the flange 26 is perforated immediately adjacent these points, likewise for the installation of nut plates.

The panel i6 is provided with stiffening beads 25 and 28, with leg apertures 21' to 39 inclusive, and with apertures 3i and 32 for receiving back sup-porting brackets. The metal bordering these apertures is bent slightly out of the plane of the panel to stifien the edges of the sheet metal at those points, which is common practice.

metal, and a portion of the Wall is cut away at their upper ends, as indicated by the numeral 36, to facilitate the bucking of rivets, or the tightening of nuts, whichever may be used.

After installation of all four legs, the panel i5 is placed in the position shown in Figure 5, and

its peripheral surface is spot welded to the flange 20, as indicated at 3?. A rigid four-legged weight supporting unit is thus formed.

The chair back illustrated in Figures 4, 5, and 7 is made as a sub-assemby, A back panel 38 is j beaded,as shown in Figure 7, and is riveted to v the upper ends of a pair of leaf spring type back supporting brackets 39 and ill. 'sembly is then secured to the rigid, box-type,

The back asweight supporting platform by studs 4| passing I through the brackets 35} and 4B, and into nut plates s2 and i3 mounted on the pan bottom, and nut plates 44 and 45 mounted on the flange 20.

In Figure 5, padding and upholstery for the chair seat are merely indicated by dotted lines. Figure 8, however, shows in detail one manner of upholstering the seat. A sponge rubber mat 4G is laid over the pan, and upholstery material 47 is laid over this mat. The edges of the upholstery material are reverse turned, as at 48, and are secured to the panel it by means of suitable wire clips 49 passing through the upholstery material and through the panel it.

Figure 9 shows an embodiment of the invention in which the rigid weight supporting platform includes a drawn sheet metal pan 58 but this pan has an integral in-turned flange 5!, instead of the out-turned flange of the embodiment previ ously described. In this case the panel is secured to the flange of the pan by means of rivets 53. This panel 52 is provided with leg apertures which closely flt the tubular metal legs 54. The legs have a plate 55 welded or otherwise secured to their upper ends. During assembly, the leg plates 55 are riveted to the pan bottom in positions spaced slightly inward from the sidewalls of the pan. The panel 52 is then slipped over the installed legs and is riveted in. position, as shown. The edge of the leg apertures is then preferably welded or brazed directly to the adjacent portion of each leg, as indicated at 55, thus rigidly anchoring the legs to the weight supporting platform, and forming a table underiraine.

To complete this table, a suitable top 5'1, of wood or other suitable material is secured to the pan bottom by means of screws 53 installed through access holes 5 23 and E5) in the panel 52.

Figure 10 shows the same type of rigid box-type stressed skin structure as that illustrated in Figure 9, but the legs are installed in a different manner. In this case hat section stringers =3! and 62 are rigidly positioned inside the box type structure in line with the points at which the legs are to be installed. These stringers are riveted to the pan bottom by rivets 53 and 54 prior to installation of the panel 68. After this panel has been installed by .means of the rivets 53, legs 65 are installed by means of rivets passing through leg flanges Bl, through the panel 53, and through the lower flanges of the hat sections El and It will be seen that with this construction the legs are attached to the weight supporting platform in fully as rigid a manner as in the construction illustrated in Figure 9. The legs in the Figure 10 construction may be tapered or of any other desired shape.

Figure 11 illustrates a rigid weight supporting platform made up of a drawn sheet metal pan H3, having integral continuous sidewalls ll, and an integral continuous outturned flange '12, plus a sheet metal panel '53, the edge surface of which is spot welded or otherwise rigidly secured to the flange 12. This particular platform is sup ported by centrally located legs i l, the number of legs depending on the length of the platform. Near its upper end each leg is provided with a plurality of radially extending brackets 75. While other types of brackets maybe used, the one illusapertures to receive these studs '19, and the table top is anchored firmly to its underframe by means of nuts 8!), installed through suitably located access holes 8! and 82 in the panel 13. Any suitable base 83 may be used to support the leg 74.

Figure 13 discloses the invention embodied in a theatre seat. Ihe basic structure is the same, and includes the drawn pan having a bottom 84, sidewalls 85,'and flanges 86. Prior to installation of the panel Bl, a suitable compression member 88 is rigidly secured to the pan bottom 84 by spot Welding or riveting. The compression member shown is of I cross section, but other shapes may be used as well. Next, the edges of the panel 87 are secured to the flange 85. Finally, hinge members as, one under each compression member 88, are riveted to the structure by rivets passing through the hinge member, through the panel 87, and through flanges 96 on the compression member. Suitable upholstery may then be applied, as previously described in connection with the chair of Fig. 5, and as illustrated in Fig. 7.

From the above description it will be seen that I have provided a light weight, easily fabricated weight supporting platform which may be used in various ways in connection with the building of metal furniture. Having described the invention with sufilcient clarity to enable one familiar with the art to construct and use it, I claim:

1. An article of furniture comprising: a hollow horizontal box-like structure of sheet metal having top and bottom panels, and sidewalls rigidly connecting said panels in spaced relation; a passage in the bottom panel for embracing a leg; and an upright supporting leg having its upper end located inside said box-like struc-' ture adjacent said top panel, said leg extending downward through said passage; and means securing the upper portion of said leg to the boxlike structure at spaced points on the leg.

2. An article of furniture as described in claim 1 in which at least a portion of said leg near its upper end is secured to a sidewall of the box-like structure at spaced points on the leg.

3. An article of furniture comprising: a sheet metal pan having a substantially flat bottom, integral side walls, and a continuous flange integral with said side Walls and lying in a plane spaced from and substantially parallel to the plane in which said bottom lies; a planar sheet metal panel having a major portion of its peripheral edge rigidly secured to said flange, the pan and attached panel together forming a rigid box-like structure; a passage in said panel affording open communication with the interior of said box-like structure; and an upright supporting leg having its upper end projecting through said passage substantially at right angles to the pane1 and secured to the box-like structure at vertically, spaced points on the leg, including a connectionto a side wall of the pan.

4. A unit as described in claim 3, and a back supporting bracket rigidly secured to said boxlike structure at two horizontally spaced points, and having its remaining portion extending upward adjacent oneside wall of the box-like structure to form a portion of a back rest.

5. ,A chair comprising: a hollow box-like horizontal seatstructure of sheet metal having top and bottom panels, and side walls rigidly connecting said panels in vertically spaced relation; passages in the bottom panel for receiving legs; legs extending through said passages into the interior 6 of the box-like structure and rigidly secured thereto; a back supporting bracket having one end and an adjacent intermediate portion secured to said seat structure at fore and aft spaced points, and its remaining portion extending upward adjacent the rear edge of said seat structure to form a portion of a back rest.

6. The invention described in claim 5 in which the said one end and adjacent intermediate portion of the back supporting bracket are rigidly secured to the box-like structure at points spaced fore and aft of said box-like structure as well as at different levels within the same.

'7. A chair comprising: a rigid box-like seat structure which includes a thin sheet metal pan having an integral depending side wall, and a sheet metal panel having at least a major portion of its periphera1 edge secured to said sidewall; passages in the panel for receiving legs; legs extending through said passages into the interior of the box-like structure and rigidly secured to the pan; a back supporting bracket having one end and an adjacent intermediate por tion secured to the seat structure at fore and aft spaced points and its remaining portion extending upward adjacent the rear edge of said boxlike seat structure; and a back panel secured to the upwardly extending portion of said bracket.

8. A metal chair comprising: a rigid horizontal box-like seat structure which includes a thin sheet metal pan having an integral depending continuous sidewall, and a flat sheet metal panel having a major portion of its peripheral edge rigidly secured to said sidewall; passages in the panel for legs; upright legs extending through said passages and rigidly secured to the pan; a back supporting bracket having one of its ends rigidly secured to the pan, having an intermediate portion secured to the panel near its periphery, and having its remaining portion extending upward adjacent the rear edge of the seat structure; and a metal pane1 rigidly secured to the upwardly extending portion of said bracket.

9. In chair construction, a pan formed of sheet material and having a bottom and integral de maining portion extending upward adjacent the rear edge of the box-like seat structure to form at least a portion of a back rest.

WILLIAM F. GRABENDIKE.

References Cited in the file of this patent A UNITED STATES PATENTS Number Name Date D. 155,727 Paden Oct. 25, 1949 1,178,610 Weiss Apr. 11, 1916 1 1,319,400 Loveland Oct. 21, 1919 1,387,315 Schaub Aug. 9, 1921 2,267,306 Panzer Dec. 23, 1941 2,456,79 1 Richardson Dec. 21, 1948 2,471,740 Hamilton May 31, 1949 

